I. Field of the Invention
The present invention relates generally to the field of sprayers which are carried on a back of a user. In particular, it relates to backpack sprayers with replaceable containers of premixed spray to avoid danger to users and to the environment from improper mixing, spilling and handling of spray materials.
II. Description of the Prior Art
Previous backpack sprayers have had containers in which spray materials and inert host liquids are mixed while the containers are attached to backpack-carrying and hand-spraying devices. Conventional backpack sprayers have spray containers with a large opening for inserting spray materials and liquids for mixing in the containers. Mixing spray materials and host liquids in containers on assembled backpack sprayers has allowed such hazards as (a) mixing dangerous proportions of toxic spray materials; (b) spilling spray materials on the ground, on spraying equipment, on clothes and on individuals directly; (c) inhaling spray fumes, mist and dust; (d) starting fires; (e) misuse of spray materials; and (f) variously exposing humans, other animals and plant life to hazardous spray materials.